The present invention relates to a virtual shape generation method and a device using the same for modifying and designing the shape and the size of a product so as to correspond to those of a human body.
When a product, such as clothing adjusted to a customer, is designed as not a custom-made product but a mass production product for a group (a specific customer bracket), a group having a similar shape is extracted from among a distribution map of a plurality of three-dimensional human body shapes to design the product that is adjusted to the group. In this case, not only product design for the average shape representing the group, but also compatibility evaluation of the product to a virtual shape located in the periphery of the variations of the group must be needed. To achieve this, there are required:
(1) creation of the distribution map of a plurality of three-dimensional human body shapes that are described using numerical data;
(2) creation of a virtual shape located in the periphery of the distribution map; and
(3) a consistent method and a device using the same for realizing this virtual shape.
Particularly, since the distribution of the three-dimensional human body shapes cannot be sufficiently represented by means of a linear distribution such as one distributed in a xe2x80x9csmaller to largerxe2x80x9d manner, multidimensional distribution map in which the shape and the size of the human body are represented must be derived. For example, in a linear distribution such as one distributed in the xe2x80x9csmaller to largerxe2x80x9d manner, a person having xe2x80x9cthe shortest height, the shortest waist girth, the shortest legs, and the smallest head among the groupxe2x80x9d at the same time and a person having xe2x80x9cthe tallest height, the largest waist girth, the longest legs, and the largest head among the groupxe2x80x9d at the same time stand on the opposite extremes of the group. However, those having such characteristics hardly exist. Accordingly, there have been expected the consistent generation method and generation device for computing and realizing the virtual shape located in the periphery of the distribution obtained after evaluating the shape and the size of each part of the human body in a multidimensional manner.
As a method for obtaining the distribution map of three-dimensional human body shapes, an art is known in which, by re-describing the human body shape using a B-spline function, the distribution is obtained using the parameter of the function (Taizou Kishimoto, Susumu Kureno, Takao Kurokawa, and Akihiro Shinozaki: Three-dimensional human body shape modeling for clothing CAD, 22nd image engineering conference, pp.235-238, 1991). However, this art only deals with characteristics of the human body as a linear distribution and there is no reference to a method for deriving a multidimensional shape distribution map.
On the other hand, in a method which is already disclosed by the inventors of the present invention (Masaaki Mochimaru, Makiko Kouchi, Yukio Fukui, and Emiko Tsutsumi, Classification of 3D foot shape based on inter-shape distance using the FFD method, Japanese Journal of Ergonomics, 33(4), pp.229-234, 1997), instead of re-describing the human body shape using the function system, characteristics of the human body can be understood as the multidimensional distribution. However, the method using the FFD by Mochimaru, et al. only solves the above problem (1) and neither problems (2) nor (3).
As the method for computing the virtual shape on the distribution map, methods for computing the average shape and the standard deviation shape are disclosed in the article by the above Kishimoto, et al. However, since, as described above, after all, this method computes the standard deviation shape based on the linear distribution of the human body shape characteristics, it cannot compute the standard deviation shape based on the multidimensional human body distribution, which is a feature of the present invention.
Furthermore, this method requires a shape to be re-described using the B-spline function based on the coordinate data of the shape obtained by a shape measurement unit. In addition, in order to accurately describe the shape using the function system, an artifice, such as one in which the number of control points of the spline function must be added in accordance with the sizes of concave and convex parts of the shape, must be needed. This leads to a major problem that a large amount of preprocessing is required.
In the average shape generation method proposed by the inventors of the present invention (Japanese Patent No. 3,106,177, method and device for generating average shape of a plurality of three-dimensional shapes), there is no above mentioned preprocessing problem. However, this method is dedicated to computation of the average shape and there is no reference to computation of the virtual shape in the periphery of the shape distribution map.
The present invention is made to solve the foregoing three problems, that is,
(1) creation of the distribution map of a plurality of three-dimensional human body shapes that are represented using numerical data;
(2) computation of a virtual shape that is located in the periphery of the distribution map; and
(3) provision of a consistent method and device for realizing the virtual shape.
In a method in which three-dimensional shape data of a plurality of people is obtained by measuring the body shape thereof, a multidimensional distribution map is formed based on the three-dimensional shape data of the plurality of people, and a virtual shape located on the periphery of the multidimensional distribution map is formed, whereby the virtual shape is generated, the method for generating the virtual shapes of the plurality of three-dimensional shapes is characterized in that a space distortion function which mutually distorts the three-dimensional shape data of the plurality of people using the free form deformation method is computed a multidimensional distribution map of the three-dimensional shape data of the plurality of people is generated and a virtual shape existing at an arbitrary location of the multidimensional distribution map is derived.
In a device for generating a virtual shape on a distribution map of a plurality of three-dimensional shapes comprising a three-dimensional shape measurement unit for measuring human shapes and outputting the measured human shapes as three-dimensional shape data of a plurality of people, a virtual shape forming unit for forming a multidimensional distribution map based on the three-dimensional shape data of the plurality of people and forming the virtual shape located in the periphery of the multidimensional distribution map, and a three-dimensional realizing unit for realizing numerical data from the virtual shape forming unit, the device for generating virtual shapes of the plurality of three-dimensional shapes is characterized in that the virtual shape forming unit has functions such that a space distortion function which mutually distorts the three-dimensional data of the plurality of people is computed using the free form deformation method, a multidimensional distribution map of the three-dimensional shape data of the plurality of people is generated based on the magnitude of the space distortion, and the virtual shape of an arbitrary location of the multidimensional distribution map is derived.